This image is not unknown, I found it in two different albums so far (in different sizes), so I guess it was traded and maybe sold aswell. Still it is unkown to many and it does not need many words as its powerful enough to speak for itself.

And I looked, and behold a pale horse: and his name that sat on him was Death, and Hell followed with him. And power was given unto them over the fourth part of the earth, to kill with sword, and with hunger, and with death, and with the beasts of the earth.